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Present hectic times do not allow the foundrymen to test various modifications of gating system in real production due to lack of time and efficiency of production phase. When testing of tens or hundreds of modifications is needed, simulation software MAGMA5 and its optimization procedure comes into place. This article deals with choosing the best design of gating system which will ensure the filling of the sprue as soon as possible together with possible shortening of pouring time on Disamatic line. Soonest filling of the sprue will ensure that no air is entraped in the molten metal which is entering the cavity of the mold and no air bubbles would occur in the final casting after pouring. With this goal achieved, foundry can secure the production of castings. There is a big chance chance to decrease the pouring time of the mold, which will make the production more effective.

The naturally pressurized gating system appears to be an appropriate solution for reoxidation reduction, but this type of gating system can result in supercritical melt velocity. The paper is focused on the determination of the unconventional elements effect in the gating system on the melt velocity and melt flow and their influence on the mechanical properties and microstructure. In experimental works was observed the influence of dimensioned gate, foam filters with 10 and 30 ppi density, trident gate and combination of trident gate and vortex element. Melt velocity was observed by simulation software and via velocity measurement by contact method in the mold during casting. Melt flow was analyzed by simulation software and water model experiment. Experimental casts have been made for the purpose of evaluating mechanical properties and microstructure determination. The best results were achieved by 30 ppi foam filter.

Bottom-up gated filling system was performed to produce worm wheel through a sand casting of zinc alloy. It was a symmetrical design in which two worm wheels were cast at once, the worm wheel was erected in the direction of gravity and had a gating system in which molten zinc alloy were poured from below. The recovery rate of the designed mold cavity was 60%. Casting analysis was performed to check that the worm wheel was sequentially filled without turbulent flow as the molten zinc alloy passed through the gate. Though the speed of the molten zinc alloy initially poured was unstable, it became stabilized while maintaining a constant speed due to the continuous inflow. The results of directional solidification were confirmed. An integrated mold cavity pattern was fabricated by 3D printer, and sand mold were manufactured accordingly. A sound worm wheel without defects could be fabricated through sand casting.

The article presents the attempt to optimize a gating system to produce cast steel castings. It is based on John Campbell’s theory and presents the original results of computer modelling of typical and optimized gating systems for cast steel castings. The current state-of-the-art in cast steel casting foundry was compared with several proposals of optimization. The aim was to find a compromise between the best, theoretically proven gating system version, and a version that would be affordable in industrial conditions. The results show that it is possible to achieve a uniform and slow pouring process even for heavy castings to preserve their internal quality.

Casting process design is crucial in manufacturing; however, traditional design workflows are time-consuming and seriously reliant on the experience and expertise of designers. To overcome these challenges, database technology has emerged as a promising solution to optimize the design process and enhance efficiency. However, conventional database storing process cases often lack adequate parametric information, limiting their ability to support intelligent and automated design. Thus, this study has developed a casting process database based on parametric case modeling, enabling the rapid design of casting processes for new parts using case-based reasoning (CBR). The database framework was designed to organize process cases into four distinct information modules, allowing for structured and separated storage. Data unit associations were established between these modules to ensure the completeness and scalability of process information. The database stores sufficient parametric information to describe key process characteristics and multidimensional elements. This includes the detailed structural parameters of parts, calculated based on the accurate analysis of their structural features. A process cost estimation model was incorporated to calculate and record direct process costs, enabling the effective comparison and ranking of various process plans for the same part. Additionally, the parametric model of the gating system is stored to support the transfer of processes between similar parts. The functionality and effectiveness of the proposed database were visually validated through a case study on the process design of an actual casting part. The results indicate that the database significantly improves efficiency and ensures the accuracy of CBR-based process design while optimizing the reuse of design knowledge and expertise. The developed database achieved a 90% reduction in design time compared to conventional methods.

One of the main reason for decreased internal homogeneity of aluminium alloy castings is reoxidation. The resulting products of reoxidation are doubled oxides, so called \"bifilms\". Submitted paper deals with optimization of gating system design in order to reduce reoxidation processes taking place in mold cavity. Experimental work compares and evaluates three gating systems designs based on non-pressurized and naturally pressurized principles. Unconventional spin trap extension of runner was used in third design. Among the evaluated aspects were: mechanical properties, hot tearing index, visual inspection of average porosity amount, numerical simulation of velocity, turbulence and oxide amount. Paper aim is also to clarify the reoxidation phenomenon by visualization with the aid of ProCAST numerical simulation software. Results of mechanical properties and hot tear index clearly confirmed the positive effect of the naturally pressurized gating system with applied element for velocity reduction.

Additive manufacturing (AM) is accepted as a transformative technology for rapid production of parts based on digital models through direct printing of a range of materials (e.g., metals, polymers, and ceramics). Recent advancements in the binder-jetting AM process (i.e., 3D sand-printing (3DSP)) enables direct production of sand molds and cores for metal casting. AM has been attractive to manufacturers due to the ability to produce complex and customized parts in low batch production. Traditional mold design for gravity castings experience higher scrap rates due to challenges in controlling turbulence and air entrapment. In this research, mathematically designed sprue geometries that can be produced via 3DSP are presented along with their effect on mechanical and metallurgical properties of castings through numerical modeling, computational simulation, and experimental validation. The casting properties are contrasted to conventional straight sprue castings for two different alloys: aluminum alloy 319 and gray cast iron class 30. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), computed tomography scanning (CT), and 3-point bending tests are performed to characterize microstructure, casting defects, elemental composition, and mechanical properties for castings of each gating system design. For aluminum alloy 319, a statistically significant increase of 10% in flexural strength was found using the conical-helix sprue geometry as well as a reduction of 25% in casting defects. In gray cast iron class 30, no statistically significant differences are found between the flexural strength of the conical-helix and benchmark straight sprue as expected in a short freezing range alloy.

Submitted work deals with the possibilities of reducing reoxidation by improved gating system design. The result of the reoxidation is the of furled oxide layers – bifilms. During experimental works, non-pressurized and naturally pressurized gating systems designs were introduced and evaluated. Mechanical properties, fracture area, hot tearing index, bifilm index and EDX analysis were used during evaluation. Paper aim is also to clarify the reoxidation phenomenon by visualization with the aid of ProCAST numerical simulation software. Achieved results clearly confirmed the positive effect of the naturally pressurized gating system, main emphasis needs to focus on finding the proper way to reduce the melt velocity. By using vortex element extension at the end of the runner was achieved positive results in term of reoxidation suppression.

Selection of an appropriate gating system for a consumable pattern is a long and time-consuming process that requires considerable effort. Advanced design technologies can be used to design the gating system and to simulate the casting process based on the design. Simulation and design of the gating system allow detection of types of defects in the casting at the development stage. Parametrical changing of the gating system 3D model and variation of its characteristics, and repeated simulation of cooling, crystallization and mold filling processes can provide high quality casting.

This article presents the results of experiments on the optimization of down sprue geometry in the process of pouring sand molds. Theoretical assumptions and computer simulation tests are presented. The starting point was the theory and experience of gas entrapment caused mainly by a poorly designed gating system and the down sprue. Simulations were performed using Magmasoft software. First, initial studies were carried out to determine how the geometry (mainly the channel cross-section) of the sprue affects the problem, and then a detailed experiment was carried out on the so-called ‘short sprue’ version. The air entrapment process was analyzed, as were the parameters of the liquid alloy flow that passes through the analyzed channels. Nine geometric versions of the sprue were proposed and analyzed, and the results allowed us to conclude which sprue geometry is the best from the point of view of minimization of the gas entrapment problem.